feat: collect subjects about in toto statements that contain other pr…

…edicates (in-toto#49)

To date Archivista has been limited to archive DSSE envelopes that
contain in-toto statements whose predicate is a Witness attestation
collection.

This commit introduces a change that allows Archivista to collect
information about DSSE envelopes that contain in-toto statements with
any arbitrary predicate.

Parsers and Storers can be added to collect more refined information
about these other predicates as we seek to add more support for them.

internal/metadatastorage/attestationcollection/parserstorer.go

@@ -0,0 +1,69 @@
+// Copyright 2023 The Archivista Contributors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package attestationcollection
+
+import (
+	"context"
+	"encoding/json"
+
+	"github.com/testifysec/archivista/ent"
+	"github.com/testifysec/archivista/internal/metadatastorage"
+	"github.com/testifysec/go-witness/attestation"
+)
+
+const (
+	Predicate = "https://witness.testifysec.com/attestation-collection/v0.1"
+)
+
+// attestation.Collection from go-witness will try to parse each of the attestations by calling their factory functions,
+// which require the attestations to be registered in the go-witness library.  We don't really care about the actual attestation
+// data for the purposes here, so just leave it as a raw message.
+type ParsedCollection struct {
+	attestation.Collection
+	Attestations []struct {
+		Type        string          `json:"type"`
+		Attestation json.RawMessage `json:"attestation"`
+	} `json:"attestations"`
+}
+
+func Parse(data []byte) (metadatastorage.Storer, error) {
+	parsedCollection := ParsedCollection{}
+	if err := json.Unmarshal(data, &parsedCollection); err != nil {
+		return parsedCollection, err
+	}
+
+	return parsedCollection, nil
+}
+
+func (parsedCollection ParsedCollection) Store(ctx context.Context, tx *ent.Tx, stmtID int) error {
+	collection, err := tx.AttestationCollection.Create().
+		SetStatementID(stmtID).
+		SetName(parsedCollection.Name).
+		Save(ctx)
+	if err != nil {
+		return err
+	}
+
+	for _, a := range parsedCollection.Attestations {
+		if err := tx.Attestation.Create().
+			SetAttestationCollectionID(collection.ID).
+			SetType(a.Type).
+			Exec(ctx); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}

internal/metadatastorage/mysqlstore/mysql.go

@@ -28,7 +28,8 @@ import (
 	"github.com/go-sql-driver/mysql"
 	"github.com/networkservicemesh/sdk/pkg/tools/log"
 	"github.com/testifysec/archivista/ent"
-	"github.com/testifysec/go-witness/attestation"
+	"github.com/testifysec/archivista/internal/metadatastorage"
+	"github.com/testifysec/archivista/internal/metadatastorage/parserregistry"
 	"github.com/testifysec/go-witness/cryptoutil"
 	"github.com/testifysec/go-witness/dsse"
 	"github.com/testifysec/go-witness/intoto"
@@ -115,17 +116,6 @@ func (s *Store) withTx(ctx context.Context, fn func(tx *ent.Tx) error) error {
 	return nil
 }
 
-// attestation.Collection from go-witness will try to parse each of the attestations by calling their factory functions,
-// which require the attestations to be registered in the go-witness library.  We don't really care about the actual attestation
-// data for the purposes here, so just leave it as a raw message.
-type parsedCollection struct {
-	attestation.Collection
-	Attestations []struct {
-		Type        string          `json:"type"`
-		Attestation json.RawMessage `json:"attestation"`
-	} `json:"attestations"`
-}
-
 func (s *Store) Store(ctx context.Context, gitoid string, obj []byte) error {
 	envelope := &dsse.Envelope{}
 	if err := json.Unmarshal(obj, envelope); err != nil {
@@ -142,9 +132,13 @@ func (s *Store) Store(ctx context.Context, gitoid string, obj []byte) error {
 		return err
 	}
 
-	parsedCollection := &parsedCollection{}
-	if err := json.Unmarshal(payload.Predicate, parsedCollection); err != nil {
-		return err
+	predicateParser, ok := parserregistry.ParserForPredicate(payload.PredicateType)
+	var predicateStorer metadatastorage.Storer
+	if ok {
+		predicateStorer, err = predicateParser(payload.Predicate)
+		if err != nil {
+			return fmt.Errorf("unable to parse intoto statements predicate: %w", err)
+		}
 	}
 
 	err = s.withTx(ctx, func(tx *ent.Tx) error {
@@ -240,19 +234,8 @@ func (s *Store) Store(ctx context.Context, gitoid string, obj []byte) error {
 			return err
 		}
 
-		collection, err := tx.AttestationCollection.Create().
-			SetStatementID(stmt.ID).
-			SetName(parsedCollection.Name).
-			Save(ctx)
-		if err != nil {
-			return err
-		}
-
-		for _, a := range parsedCollection.Attestations {
-			if err := tx.Attestation.Create().
-				SetAttestationCollectionID(collection.ID).
-				SetType(a.Type).
-				Exec(ctx); err != nil {
+		if predicateStorer != nil {
+			if err := predicateStorer.Store(ctx, tx, stmt.ID); err != nil {
 				return err
 			}
 		}

internal/metadatastorage/parser.go

@@ -0,0 +1,27 @@
+// Copyright 2023 The Archivista Contributors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package metadatastorage
+
+import (
+	"context"
+
+	"github.com/testifysec/archivista/ent"
+)
+
+type ParserFunc func([]byte) (Storer, error)
+
+type Storer interface {
+	Store(ctx context.Context, tx *ent.Tx, stmtID int) error
+}

internal/metadatastorage/parserregistry/registry.go

@@ -0,0 +1,31 @@
+// Copyright 2023 The Archivista Contributors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package parserregistry
+
+import (
+	"github.com/testifysec/archivista/internal/metadatastorage"
+	"github.com/testifysec/archivista/internal/metadatastorage/attestationcollection"
+)
+
+var (
+	parsersByPredicate = map[string]metadatastorage.ParserFunc{
+		attestationcollection.Predicate: attestationcollection.Parse,
+	}
+)
+
+func ParserForPredicate(predicate string) (metadatastorage.ParserFunc, bool) {
+	pf, ok := parsersByPredicate[predicate]
+	return pf, ok
+}